CHARACTERISTICS OF HYDROCARBON SOURCE ROCKS IN THEJURASSIC SHEMSHAK FORMATION OF KASHAN AREA, IRAN

By analyses on the organic matter abundance of hydrocarbon source rocks,the vitrinite composition and carbon isotopic features of kerogen and the features of biomarkers in the Jurassic Shemshak Formation of Kashan area,Iran,it was suggested that the kerogen types of the Shemshak source rocks be mainly sapropel-humic(Ⅱ2) and humic(Ⅲ).Most samples have evolved to overmature stages.Except for a few good source rocks,most source rocks of the Shemshak Formation are middle grade.